<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <script src="./lib/vue.js"></script>
  </head>
  <body>
    <div id="app">
      用户名：<input type="text" v-model="username" /><br />
      密码：<input type="text" v-model="password" /><br />
      <button @click="login">登录</button>
    </div>

    <script>
      new Vue({
        el: '#app',
        data: {
          username: '',
          password: ''
        },
        methods: {
          login() {
            alert(this.username + '  ' + this.password)
          }
        }
      })
    </script>
  </body>
</html>
